In Southeast Louisiana the following colorful plants do well in part shade -
shrubs - lorapetalem (burgundy foliage)
flowers - Pentas (come back some years), alstroemeria (perennial), begonias, lisianthus (come back most years), For foliage - polk-a-dot plants (hyposteses Spelling?) perennial here - red, pink or white and green foliage, coleus (annual), ajuga. Happy gardening!

Theresa,
Ipheion as a spring bulb does well to brighten a shady spot as do Hellebores. How about variegated hydrangea, Oakleaf hydrangea, Heuchera, japanese maples, Autumn moon or any chartreuse colored hosta, purple oxalis, spanish bluebells, golden creeping jenny, Persian shield, the many varieties of coleus, toad lilly, and bletilla striata to name a few. If you want instant color in the shade however, look to impatiens. Trite, maybe, but there's a reason why they're a tried and true.
Laurie

Somehow I thought Heucheras didn't do well here. Who has them growing well? Maybe I can give them a try.